A conserved proline triplet in Val-tRNA synthetase and the origin of elongation factor P
2014 (English)In: Cell reports, ISSN 2211-1247, Vol. 9, no 2, 476-483 p.Article in journal (Refereed) Published
Bacterial ribosomes stall on polyproline stretches and require the elongation factor P (EF-P) to relieve the arrest. Yet it remains unclear why evolution has favored the development of EF-P rather than selecting against the occurrence of polyproline stretches in proteins. We have discovered that only a single polyproline stretch is invariant across all domains of life, namely a proline triplet in ValS, the tRNA synthetase, that charges tRNA(Val) with valine. Here, we show that expression of ValS in vivo and in vitro requires EF-P and demonstrate that the proline triplet located in the active site of ValS is important for efficient charging of tRNA(Val) with valine and preventing formation of mischarged Thr-tRNA(Val) as well as efficient growth of E. coli in vivo. We suggest that the critical role of the proline triplet for ValS activity may explain why bacterial cells coevolved the EF-P rescue system.
Place, publisher, year, edition, pages
Cell Press , 2014. Vol. 9, no 2, 476-483 p.
Cell and Molecular Biology
IdentifiersURN: urn:nbn:se:umu:diva-97232DOI: 10.1016/j.celrep.2014.09.008ISI: 000344469100008PubMedID: 25310979OAI: oai:DiVA.org:umu-97232DiVA: diva2:773219